A variety of different systems are utilized in a healthcare environment to store, organize and retrieve different types of medical or patient related information. Typical systems are described below.
In a healthcare environment, a Picture Archiving and Communication System (PACS) concerns the archiving, communication and visualization of medical imaging and other related information, as well as with the workflow management for the generation and interpretation of such information. PACS designates the overall system composed of archives, visualization stations, image digitizers, and communication interfaces.
The expression “imaging information object” will be used to designate an image, an information object related to an image, or a set of related images and/or information objects. PACS also relates to with the problem of how to transfer imaging information objects between two systems, a source system and a destination. Generally, PACS includes a system, designated with the term “archive”, that is composed of: a storage media that stores the data of the imaging information objects, a database that stores the attributes of imaging information objects in order to retrieve their data from the storage media as a response for a query, and an interface software for communicating with peers according to a standard communication protocol.
A system, a peer within the PACS, is composed of an interface software for communicating with peers according to a standard communication protocol and a imaging information object consumer that acts on that imaging information object's data. The destination system can be for example, an archive, a printer capable of printing the data of the imaging information object on papers or films, or a viewer capable of displaying the data of the imaging information object on monitors. The source and the destination systems can be hosted by two distinct computers connected to a network or by the same computer. In the later case, the communication interface software is not necessary. The most widely used standard for communicating medical images over a network is the Digital Imaging and Communications in Medicine (DICOM) standard that has been developed by the American College of Radiology (ACR) and the National Electrical Manufacturers Association (NEMA).
FIG. 2 illustrates the image flow in PACS systems. The images are acquired by modalities, digitized if necessary, and communicated through the communication interface to the archive and one or multiple visualization stations according to a pre-configured image flow. The visualization station receives the images and stores them on a local short-term storage media. A “pre-fetch” software triggers the transfer of scheduled patients' old images, from the archive to one or multiple visualization station according to a pre-configured image flow.
PACS manages imaging information objects that are generated, visualized and interpreted in an imaging department as depicted in FIG. 3. The business of the imaging department is to deliver an imaging result to a customer who is the recipient or beneficiary of the result. The imaging process is initiated by a request for an imaging procedure for a specific patient. The imaging process result is an imaging report that is a document whose content holds the interpretation and the impressions of the radiologist. The imaging process customer, the recipient of the imaging report, is a healthcare specialist that is usually outside of the imaging department, and is involved in the patient care. To achieve one complete imaging process, from ordering to result generation, multiple steps are usually performed. These include scheduling of acquisition, image acquisition, image processing, image interpretation, report recording, report transcription and report verification. Each step may be performed by a different system. For example, a Radiology Information System (RIS) may manage scheduling of acquisition, report recording, report transcription and report verification. The PACS on the other hand, manages image visualization to enable image interpretation.
Of particular interest herein the imaging information objects generated during an imaging service, for a specific patient. These imaging information objects include images and other related information in addition to the imaging report. These imaging information objects constitute important patient's clinical and diagnostic information. Therefore they are archived for a long period and make up part of the patient's health history. They may be archived and managed by different systems. For example, images and related information are archived and managed by the PACS while the imaging report is archived and managed by the information system such as the RIS. Moreover, they are used as prior information in future patient's imaging processes. In fact, while performing an interpretation task, the imaging specialist compares current images with prior ones and consults prior reports. Therefore, it is very important for a specialist to access all relevant patient's history in order to provide optimal care.
Also, of particular interest herein is the patient identification that is used to link the imaging information objects to a specific real patient. This identification is encoded within each patient's information object. It is used by the managing system to identify all information objects that belong to a specific patient. When a system receives an information object using a communication protocol for example, it extracts the patient identification from that information object in order to internally link the object to that patient. Therefore, a system can identify, using the patient identification, all information objects belonging to a specific real patient.
Usually, systems that cooperate within the same enterprise use the same patient identification. This is achieved by sharing patient identification with messages exchanged on the network or manually. Moreover, a specific report is linked to the images via a single shared identification such as procedure identification or more commonly the order identification. Again, such identification is shared by the various systems with messages exchanged on the network or manually.
In many situations, a specific patient may have imaging information in different enterprises. An enterprise designates a hospital, a group of hospitals, an imaging center, or any institution involved in the patient care. Providing access to prior information while performing a diagnostic imaging service is necessary to ensure optimal care. Prior information may reside in a different enterprise. Prior information includes prior images. Prior images are needed to perform comparisons with newly acquired images. Prior information also includes prior reports. Prior reports are needed to access prior interpretations and results.
In addition to sharing patient information between multiple enterprises, it is important to share information from various clinical domains. Examples include access to laboratory results while performing an imaging interpretation task. Patient Electronic Health Record (EHR) designates one or multiple systems that cooperate together to provide access to the patient's health history. EHR usually provides functionalities such as query and retrieve information for a specific patient as well as publishing health information for a specific patient. (In providing the functionality of query and retrieve information, the EHR operates in a manner akin to a registry or a system having the functionality of an index/retrieve system.) Frameworks for sharing patient information between multiple enterprises and between various clinical domains are essential and central to the EHR. Of particular interest herein is that such frameworks use communication protocol and information object encoding formats that are different from those used within an imaging department. Therefore, deployed PACS cannot communicate with EHR as they cannot communicate with the EHR communication protocol. Furthermore, patient identification is not usually consistent between the imaging department and the EHR or other enterprises. Also, security requirements are commonly dissimilar when communicating information on the network between two systems that belong to the same imaging department or when communicating information on the network between a system that belongs to the imaging department and a system the does not belong to the imaging department. For example, information exchange may take place on an unsecured network within the imaging department while secure communication involving encryption or systems authentication may be needed while communicating with systems outside of the imaging department.
In the typical systems described above, it would be desirable to provide existing PACS the capability of bi-directional communication with the EHR for querying and retrieving information from other enterprises or other clinical domains as well as for submitting imaging information to the EHR.
It would also be desirable to provide existing PACS information retrieved from the EHR in a way that enables them to process the information and to integrate it within their data model and their persistence framework. This implies transforming the information into an encoding format that is acceptable for the PACS and ensuring that the information is identified with identifiers that are meaningful and consistent with those used by the PACS.
It would also be desirable to be able to communicate with various communication protocols satisfying different security requirements.